Technical writing is so important during software life cycle.
Here just list some simple examples of principles a text may obeys.
These principles are extracted from a e-book that teaches about technical writing:
1. Subjects and verbs. The agents and actions that you want to appear most important in the mind of your reader should be used as the subjects and verbs of your sentences.
2. Information flow. In each sentence, move your reader from familiar information to new information. The old information in a sentence should appear at the beginning, and the new information should appear at the end.
3. Consistent names. Don't use different words to mean the same thing, especially for technical terms.
4. Singular. In technical text especially, prefer singular to plural.To distinguish one-to-one relationships from n-to-m relationships, refer to each item in the singular, not the plural.
That's all.